Trump’s legal team is already “building a case for firing Mueller,” wrote Richard Painter in a tweet that surfaced after he appeared on Fox News Saturday.

Painter was President George W. Bush’s chief White House ethics lawyer from 2005 to 2007.

“If that happens Mike Pence will soon become the 46th President,” Painter wrote. “Trump surrogates are making up Mueller ‘conflicts’ to justify firing him. That will be yet more obstruction of justice if it happens.”

It was revealed last week that Mueller if investigating President Trump for conflict of interest over how he fired FBI Director James Comey.

Former House Speaker Newt Gingrich has run to Trump’s defense, claiming he “cannot obstruct justice” because he is the president. You may recall that while leading the House in 1998 Gingrich voted to impeach President Bill Clinton on charges of obstruction of justice and perjury. Gingrich worked as a campaign strategist for Trump. Gingrich recently said, “Republicans are delusional if they think the special counsel is going to be fair.”

Comey admitted on March 20, that the FBI was investigating Trump’s campaign team and his associates for potential collusion with Russia to influence the election. Comey also said Trump told him to “let go” of the FBI’s investigation into fired National Security Adviser Michael Flynn.

Trump has continued to claim that he is part of a “witch hunt” and that any collusion with Russian is nothing more than a hoax.

The Department of Justice appointed Mueller as special counsel to head up the Russia investigation on May 17. He previously served as director of the FBI under the Bush and Obama administrations from 2001 to 2013.

President Trump on Thursday took to Twitter and claimed that Mueller’s investigation was being “led by some very bad and conflicted people!” and said the special counsel was conducting “the single greatest witch hunt in American political history.”

Experts said earlier in the week that if Trump fires Mueller he will likely experience resignations of senior Department of Justice staff, reprisals from Congress, and the mass resignation of White House staff.

“Mueller is absolutely not compromised by his professional relationship with Comey,” said Painter on Saturday. “This is just an effort to undermine the credibility of the special counsel.”